Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c800c5c9 authored by Ralf Baechle's avatar Ralf Baechle Committed by David S. Miller
Browse files

Fix/Rewrite of the mipsnet driver]



This is Thiemo's patch.

----- Forwarded message from Thiemo Seufer <ths@networkno.de> -----

From: Thiemo Seufer <ths@networkno.de>
Date: Sat, 17 Nov 2007 22:29:13 +0000
To: netdev@vger.kernel.org
Cc: linux-mips@linux-mips.org, ralf@linux-mips.org
Subject: [PATCH, REPOST] Fix/Rewrite of the mipsnet driver
Content-Type: text/plain; charset=us-ascii

Hello All,

currently the mipsnet driver fails after transmitting a number of
packages because SKBs are allocated but never freed. I fixed that
and coudn't refrain from removing the most egregious warts.

- mipsnet.h folded into mipsnet.c, as it doesn't provide any
  useful external interface.
- Free SKB after transmission.
- Call free_irq in mipsnet_close, to balance the request_irq in
  mipsnet_open.
- Removed duplicate read of rxDataCount.
- Some identifiers are now less verbose.
- Removed dead and/or unnecessarily complex code.
- Code formatting fixes.

Tested on Qemu's mipssim emulation, with this patch it can boot a
Debian NFSroot.

Thiemo

Signed-off-by: default avatarThiemo Seufer <ths@networkno.de>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ba64f58e
Loading
Loading
Loading
Loading
+135 −68
Original line number Diff line number Diff line
@@ -4,8 +4,6 @@
 * for more details.
 */

#define DEBUG

#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
@@ -15,11 +13,93 @@
#include <linux/platform_device.h>
#include <asm/mips-boards/simint.h>

#include "mipsnet.h"		/* actual device IO mapping */
#define MIPSNET_VERSION "2007-11-17"

/*
 * Net status/control block as seen by sw in the core.
 */
struct mipsnet_regs {
	/*
	 * Device info for probing, reads as MIPSNET%d where %d is some
	 * form of version.
	 */
	u64 devId;		/*0x00 */

	/*
	 * read only busy flag.
	 * Set and cleared by the Net Device to indicate that an rx or a tx
	 * is in progress.
	 */
	u32 busy;		/*0x08 */

	/*
	 * Set by the Net Device.
	 * The device will set it once data has been received.
	 * The value is the number of bytes that should be read from
	 * rxDataBuffer.  The value will decrease till 0 until all the data
	 * from rxDataBuffer has been read.
	 */
	u32 rxDataCount;	/*0x0c */
#define MIPSNET_MAX_RXTX_DATACOUNT (1 << 16)

	/*
	 * Settable from the MIPS core, cleared by the Net Device.
	 * The core should set the number of bytes it wants to send,
	 * then it should write those bytes of data to txDataBuffer.
	 * The device will clear txDataCount has been processed (not
	 * necessarily sent).
	 */
	u32 txDataCount;	/*0x10 */

	/*
	 * Interrupt control
	 *
	 * Used to clear the interrupted generated by this dev.
	 * Write a 1 to clear the interrupt. (except bit31).
	 *
	 * Bit0 is set if it was a tx-done interrupt.
	 * Bit1 is set when new rx-data is available.
	 *    Until this bit is cleared there will be no other RXs.
	 *
	 * Bit31 is used for testing, it clears after a read.
	 *    Writing 1 to this bit will cause an interrupt to be generated.
	 *    To clear the test interrupt, write 0 to this register.
	 */
	u32 interruptControl;	/*0x14 */
#define MIPSNET_INTCTL_TXDONE     (1u << 0)
#define MIPSNET_INTCTL_RXDONE     (1u << 1)
#define MIPSNET_INTCTL_TESTBIT    (1u << 31)

	/*
	 * Readonly core-specific interrupt info for the device to signal
	 * the core. The meaning of the contents of this field might change.
	 */
	/* XXX: the whole memIntf interrupt scheme is messy: the device
	 * should have no control what so ever of what VPE/register set is
	 * being used.
	 * The MemIntf should only expose interrupt lines, and something in
	 * the config should be responsible for the line<->core/vpe bindings.
	 */
	u32 interruptInfo;	/*0x18 */

	/*
	 * This is where the received data is read out.
	 * There is more data to read until rxDataReady is 0.
	 * Only 1 byte at this regs offset is used.
	 */
	u32 rxDataBuffer;	/*0x1c */

#define MIPSNET_VERSION "2005-06-20"
	/*
	 * This is where the data to transmit is written.
	 * Data should be written for the amount specified in the
	 * txDataCount register.
	 * Only 1 byte at this regs offset is used.
	 */
	u32 txDataBuffer;	/*0x20 */
};

#define mipsnet_reg_address(dev, field) (dev->base_addr + field_offset(field))
#define regaddr(dev, field) \
  (dev->base_addr + offsetof(struct mipsnet_regs, field))

static char mipsnet_string[] = "mipsnet";

@@ -29,32 +109,27 @@ static char mipsnet_string[] = "mipsnet";
static int ioiocpy_frommipsnet(struct net_device *dev, unsigned char *kdata,
			int len)
{
	uint32_t available_len = inl(mipsnet_reg_address(dev, rxDataCount));

	if (available_len < len)
		return -EFAULT;

	for (; len > 0; len--, kdata++)
		*kdata = inb(mipsnet_reg_address(dev, rxDataBuffer));
		*kdata = inb(regaddr(dev, rxDataBuffer));

	return inl(mipsnet_reg_address(dev, rxDataCount));
	return inl(regaddr(dev, rxDataCount));
}

static inline ssize_t mipsnet_put_todevice(struct net_device *dev,
static inline void mipsnet_put_todevice(struct net_device *dev,
	struct sk_buff *skb)
{
	int count_to_go = skb->len;
	char *buf_ptr = skb->data;

	outl(skb->len, mipsnet_reg_address(dev, txDataCount));
	outl(skb->len, regaddr(dev, txDataCount));

	for (; count_to_go; buf_ptr++, count_to_go--)
		outb(*buf_ptr, mipsnet_reg_address(dev, txDataBuffer));
		outb(*buf_ptr, regaddr(dev, txDataBuffer));

	dev->stats.tx_packets++;
	dev->stats.tx_bytes += skb->len;

	return skb->len;
	dev_kfree_skb(skb);
}

static int mipsnet_xmit(struct sk_buff *skb, struct net_device *dev)
@@ -69,18 +144,20 @@ static int mipsnet_xmit(struct sk_buff *skb, struct net_device *dev)
	return 0;
}

static inline ssize_t mipsnet_get_fromdev(struct net_device *dev, size_t count)
static inline ssize_t mipsnet_get_fromdev(struct net_device *dev, size_t len)
{
	struct sk_buff *skb;
	size_t len = count;

	skb = alloc_skb(len + 2, GFP_KERNEL);
	if (!len)
		return len;

	skb = dev_alloc_skb(len + NET_IP_ALIGN);
	if (!skb) {
		dev->stats.rx_dropped++;
		return -ENOMEM;
	}

	skb_reserve(skb, 2);
	skb_reserve(skb, NET_IP_ALIGN);
	if (ioiocpy_frommipsnet(dev, skb_put(skb, len), len))
		return -EFAULT;

@@ -92,50 +169,42 @@ static inline ssize_t mipsnet_get_fromdev(struct net_device *dev, size_t count)
	dev->stats.rx_packets++;
	dev->stats.rx_bytes += len;

	return count;
	return len;
}

static irqreturn_t mipsnet_interrupt(int irq, void *dev_id)
{
	struct net_device *dev = dev_id;

	irqreturn_t retval = IRQ_NONE;
	uint64_t interruptFlags;

	if (irq == dev->irq) {
		retval = IRQ_HANDLED;

		interruptFlags =
		    inl(mipsnet_reg_address(dev, interruptControl));

		if (interruptFlags & MIPSNET_INTCTL_TXDONE) {
			outl(MIPSNET_INTCTL_TXDONE,
			     mipsnet_reg_address(dev, interruptControl));
			/* only one packet at a time, we are done. */
	u32 int_flags;
	irqreturn_t ret = IRQ_NONE;

	if (irq != dev->irq)
		goto out_badirq;

	/* TESTBIT is cleared on read. */
	int_flags = inl(regaddr(dev, interruptControl));
	if (int_flags & MIPSNET_INTCTL_TESTBIT) {
		/* TESTBIT takes effect after a write with 0. */
		outl(0, regaddr(dev, interruptControl));
		ret = IRQ_HANDLED;
	} else if (int_flags & MIPSNET_INTCTL_TXDONE) {
		/* Only one packet at a time, we are done. */
		dev->stats.tx_packets++;
		netif_wake_queue(dev);
		} else if (interruptFlags & MIPSNET_INTCTL_RXDONE) {
			mipsnet_get_fromdev(dev,
				    inl(mipsnet_reg_address(dev, rxDataCount)));
			outl(MIPSNET_INTCTL_RXDONE,
			     mipsnet_reg_address(dev, interruptControl));

		} else if (interruptFlags & MIPSNET_INTCTL_TESTBIT) {
			/*
			 * TESTBIT is cleared on read.
			 * And takes effect after a write with 0
			 */
			outl(0, mipsnet_reg_address(dev, interruptControl));
		} else {
			/* Maybe shared IRQ, just ignore, no clearing. */
			retval = IRQ_NONE;
		outl(MIPSNET_INTCTL_TXDONE,
		     regaddr(dev, interruptControl));
		ret = IRQ_HANDLED;
	} else if (int_flags & MIPSNET_INTCTL_RXDONE) {
		mipsnet_get_fromdev(dev, inl(regaddr(dev, rxDataCount)));
		outl(MIPSNET_INTCTL_RXDONE, regaddr(dev, interruptControl));
		ret = IRQ_HANDLED;
	}
	return ret;

	} else {
out_badirq:
	printk(KERN_INFO "%s: %s(): irq %d for unknown device\n",
	       dev->name, __FUNCTION__, irq);
		retval = IRQ_NONE;
	}
	return retval;
	return ret;
}

static int mipsnet_open(struct net_device *dev)
@@ -144,18 +213,15 @@ static int mipsnet_open(struct net_device *dev)

	err = request_irq(dev->irq, &mipsnet_interrupt,
			  IRQF_SHARED, dev->name, (void *) dev);

	if (err) {
		release_region(dev->base_addr, MIPSNET_IO_EXTENT);
		release_region(dev->base_addr, sizeof(struct mipsnet_regs));
		return err;
	}

	netif_start_queue(dev);

	/* test interrupt handler */
	outl(MIPSNET_INTCTL_TESTBIT,
	     mipsnet_reg_address(dev, interruptControl));

	outl(MIPSNET_INTCTL_TESTBIT, regaddr(dev, interruptControl));

	return 0;
}
@@ -163,7 +229,7 @@ static int mipsnet_open(struct net_device *dev)
static int mipsnet_close(struct net_device *dev)
{
	netif_stop_queue(dev);

	free_irq(dev->irq, dev);
	return 0;
}

@@ -194,10 +260,11 @@ static int __init mipsnet_probe(struct device *dev)
	 */
	netdev->base_addr = 0x4200;
	netdev->irq = MIPS_CPU_IRQ_BASE + MIPSCPU_INT_MB0 +
		      inl(mipsnet_reg_address(netdev, interruptInfo));
		      inl(regaddr(netdev, interruptInfo));

	/* Get the io region now, get irq on open() */
	if (!request_region(netdev->base_addr, MIPSNET_IO_EXTENT, "mipsnet")) {
	if (!request_region(netdev->base_addr, sizeof(struct mipsnet_regs),
			    "mipsnet")) {
		err = -EBUSY;
		goto out_free_netdev;
	}
@@ -217,7 +284,7 @@ static int __init mipsnet_probe(struct device *dev)
	return 0;

out_free_region:
	release_region(netdev->base_addr, MIPSNET_IO_EXTENT);
	release_region(netdev->base_addr, sizeof(struct mipsnet_regs));

out_free_netdev:
	free_netdev(netdev);
@@ -231,7 +298,7 @@ static int __devexit mipsnet_device_remove(struct device *device)
	struct net_device *dev = dev_get_drvdata(device);

	unregister_netdev(dev);
	release_region(dev->base_addr, MIPSNET_IO_EXTENT);
	release_region(dev->base_addr, sizeof(struct mipsnet_regs));
	free_netdev(dev);
	dev_set_drvdata(device, NULL);

drivers/net/mipsnet.h

deleted100644 → 0
+0 −112
Original line number Diff line number Diff line
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#ifndef __MIPSNET_H
#define __MIPSNET_H

/*
 *  Id of this Net device, as seen by the core.
 */
#define MIPS_NET_DEV_ID ((uint64_t)	   \
			     ((uint64_t) 'M' <<  0)| \
			     ((uint64_t) 'I' <<  8)| \
			     ((uint64_t) 'P' << 16)| \
			     ((uint64_t) 'S' << 24)| \
			     ((uint64_t) 'N' << 32)| \
			     ((uint64_t) 'E' << 40)| \
			     ((uint64_t) 'T' << 48)| \
			     ((uint64_t) '0' << 56))

/*
 * Net status/control block as seen by sw in the core.
 * (Why not use bit fields? can't be bothered with cross-platform struct
 *  packing.)
 */
struct net_control_block {
	/*
	 * dev info for probing
	 * reads as MIPSNET%d where %d is some form of version
	 */
	uint64_t devId;		/* 0x00 */

	/*
	 * read only busy flag.
	 * Set and cleared by the Net Device to indicate that an rx or a tx
	 * is in progress.
	 */
	uint32_t busy;		/* 0x08 */

	/*
	 * Set by the Net Device.
	 * The device will set it once data has been received.
	 * The value is the number of bytes that should be read from
	 * rxDataBuffer.  The value will decrease till 0 until all the data
	 * from rxDataBuffer has been read.
	 */
	uint32_t rxDataCount;	/* 0x0c */
#define MIPSNET_MAX_RXTX_DATACOUNT (1<<16)

	/*
	 * Settable from the MIPS core, cleared by the Net Device.  The core
	 * should set the number of bytes it wants to send, then it should
	 * write those bytes of data to txDataBuffer.  The device will clear
	 * txDataCount has been processed (not necessarily sent).
	 */
	uint32_t txDataCount;	/* 0x10 */

	/*
	 * Interrupt control
	 *
	 * Used to clear the interrupted generated by this dev.
	 * Write a 1 to clear the interrupt. (except bit31).
	 *
	 * Bit0 is set if it was a tx-done interrupt.
	 * Bit1 is set when new rx-data is available.
	 *      Until this bit is cleared there will be no other RXs.
	 *
	 * Bit31 is used for testing, it clears after a read.
	 *    Writing 1 to this bit will cause an interrupt to be generated.
	 *    To clear the test interrupt, write 0 to this register.
	 */
	uint32_t interruptControl;	/*0x14 */
#define MIPSNET_INTCTL_TXDONE     ((uint32_t)(1 <<  0))
#define MIPSNET_INTCTL_RXDONE     ((uint32_t)(1 <<  1))
#define MIPSNET_INTCTL_TESTBIT    ((uint32_t)(1 << 31))
#define MIPSNET_INTCTL_ALLSOURCES	(MIPSNET_INTCTL_TXDONE | \
					 MIPSNET_INTCTL_RXDONE | \
					 MIPSNET_INTCTL_TESTBIT)

	/*
	 * Readonly core-specific interrupt info for the device to signal the
	 * core.  The meaning of the contents of this field might change.
	 *
	 * TODO: the whole memIntf interrupt scheme is messy: the device should
	 *       have no control what so ever of what VPE/register set is being
	 *       used.  The MemIntf should only expose interrupt lines, and
	 *       something in the config should be responsible for the
	 *       line<->core/vpe bindings.
	 */
	uint32_t interruptInfo;	/* 0x18 */

	/*
	 *  This is where the received data is read out.
	 *  There is more data to read until rxDataReady is 0.
	 *  Only 1 byte at this regs offset is used.
	 */
	uint32_t rxDataBuffer;	/* 0x1c */

	/*
	 * This is where the data to transmit is written.  Data should be
	 * written for the amount specified in the txDataCount register.  Only
	 * 1 byte at this regs offset is used.
	 */
	uint32_t txDataBuffer;	/* 0x20 */
};

#define MIPSNET_IO_EXTENT 0x40	/* being generous */

#define field_offset(field) (offsetof(struct net_control_block, field))

#endif /* __MIPSNET_H */